Field of the Invention
The invention relates in general to a key structure, and more particularly to a key structure with lightweight and thinning design.
Description of the Related Art
In a conventional key structure, an elastic member provides a recovery elastic force for a key cap supported by a scissor structure to restore the key cap to its pre-pressing position. However, the scissor structure, being hard to assemble and having a longer pressing stroke, is not suitable to the keyboard with thinning design. Meanwhile, when the key cap is pressed, the downward force is transmitted to a thin film circuit board formed of bi-layer circuits by the elastic member. However, if the downward force is insufficient, it is difficult to make the bi-layer circuits come into contact, and the sensitivity will be poor. Besides, the key structure cannot be stored to reduce the structural height when the key structure is not in use. Under the current trend of ultra-thinning design of the portable computer, there is a strong need to develop a new key structure whose overall height is reduced when the portable computer is closed.